Innate Immune Function in Influenza-Associated Myopathy

流感相关肌病的先天免疫功能

基本信息

批准号：
10557027
负责人：
Benjamin L King
金额：
$ 26.19万
依托单位：
UNIVERSITY OF MAINE ORONO
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-04-05 至 2028-03-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10557027
关键词：
Acetylcysteine Acute Adhesions Antioxidants Biopsy Biosensor Chemotaxis Creatine Kinase Cues Defect Disease Embryo Exhibits Extensive Necrosis Extracellular Matrix Fiber Focal Infection Genetic Glutathione Goals Grant Hospitalization Hour Hydrogen Peroxide Immune system Individual Infection Inflammatory Response Influenza Influenza A Virus, H1N1 Subtype Influenza A virus Innate Immune System Integration Host Factors Invaded Knowledge Laboratories Ligands Link Macrophage Mediating MicroRNAs Modeling Muscle Muscle Cells Myelogenous Myocarditis Myopathy Natural Immunity Neutrophil Activation Neutrophil Infiltration Oxidative Stress Pathogenesis Pathology Pathway interactions Patients Peroxidases Population Production Regulation Reporter Reporting Respiratory Signs and Symptoms Role Sagittaria Sarcolemma Serum Severities Signal Pathway Signal Transduction Site Skeletal Muscle Symptoms System Testing Tissues Transgenes Viral Virus Virus Diseases Visualization Zebrafish biological adaptation to stress cell behavior cell growth regulation cell motility confocal imaging design extracellular gene regulatory network in vivo in vivo imaging influenza epidemic influenza infection influenza virus vaccine influenzavirus innate immune function insight migration muscle degeneration mutant neutrophil novel overexpression pathogen recruit response strength training therapy development tool transcriptome sequencing

项目摘要

PROJECT SUMMARY / ABSTRACT Skeletal muscle myopathy has been reported following infection by influenza virus. In Influenza-Associated Myopathy (IAM), a systemic influenza infection can result in acute skeletal muscle damage that ranges from non- specific degeneration to extensive necrosis. IAM is associated with high serum creatine kinase (CK) levels. During the 2009 H1N1 influenza epidemic, 62% of hospitalized patients had increased serum CK levels. Given that an estimated 9-45 million individuals acquire influenza infections annually in the US, developing new strategies to reduce muscle damage are needed as influenza vaccines are difficult to design because of unpredictable changes in viral strains within and across populations. The severity of viral disease varies between individuals and depends on how the immune system responds to infection. One roadblock to understanding the pathogenesis of IAM is that the relative contributions of the virus and host factors in vivo are not well understood. Biopsy studies cannot show the temporal dynamics of viral invasion and subsequent recruitment of neutrophils and macrophages into muscle. The zebrafish is a powerful model to study host-pathogen interactions as genetic tools can be combined with in vivo imaging of transparent embryos. My laboratory uses a recently-developed zebrafish model of influenza A virus (IAV) infection where it was shown that: 1) IAV-infected zebrafish embryos exhibited mild muscle degeneration with sarcolemma damage and compromised extracellular matrix (ECM) adhesion; and 2) neutrophils localize to sites of muscle damage in IAV-infected embryos. Our specific goal in this proposal is to determine the mechanisms through which neutrophils influence the pathology of IAM. This project will test the novel hypothesis that overactivation of neutrophils during IAV infection triggers a damaging hyperinflammatory response that contributes to myopathy. In the first aim, we will test the hypothesis that reduction in reactive oxidative species (ROS) production following IAV infection will limit damage by strengthening muscle cell-ECM adhesion, and increase survival. This will be accomplished by examining how global ROS reduction and neutrophil-specific ROS reduction alters muscle degeneration, cell-ECM adhesion, and neutrophil localization in the muscle in vivo using IAV multi-spectral fluorescent reporter (Color-flu) strains. In the second aim, we will test the hypothesis that defects in neutrophil migration following IAV infection will increase muscle degeneration, and weaken ECM adhesion. To accomplish this, we will use in vivo confocal imaging to study two zebrafish mutants with defective neutrophil migration infected with Color-flu to test our hypotheses that: 1) neutrophil invasion into skeletal muscle is reduced, and 2) muscle degeneration is increased and cell-ECM adhesion is increased over controls. One of these mutants overexpresses miR-199 in neutrophils that disrupts neutrophil migration. Proposed RNA sequencing will allow us to determine microRNA gene regulatory networks thereby allowing us to establish a link between IAM and microRNA genetic regulation. Knowledge gained through the study of IAM may inform studies of other viral-associated myopathies.

项目概要/摘要据报道，流感病毒感染后会出现骨骼肌肌病。与流感相关肌病 (IAM) 是一种全身性流感感染，可导致急性骨骼肌损伤，范围从非特异性变性至广泛坏死。 IAM 与高血清肌酸激酶 (CK) 水平相关。 2009年H1N1流感流行期间，62%的住院患者血清CK水平升高。给定据估计，美国每年有 9-4500 万人感染流感，正在开发新的流感病毒由于流感疫苗难以设计，因此需要减少肌肉损伤的策略人群内部和人群之间病毒株的不可预测的变化。病毒性疾病的严重程度因人而异个体差异，取决于免疫系统对感染的反应。理解这一点的一个障碍 IAM 的发病机制在于病毒和宿主因素在体内的相对贡献尚不清楚。活检研究无法显示病毒入侵和随后中性粒细胞募集的时间动态和巨噬细胞进入肌肉。斑马鱼是研究宿主与病原体相互作用的强大模型工具可以与透明胚胎的体内成像相结合。我的实验室使用了最近开发的甲型流感病毒 (IAV) 感染的斑马鱼模型显示：1) 感染 IAV 的斑马鱼胚胎表现出轻度肌肉退化，伴有肌膜损伤和细胞外基质（ECM）受损附着力； 2) 中性粒细胞定位于 IAV 感染胚胎的肌肉损伤部位。我们的具体目标是该提案旨在确定中性粒细胞影响 IAM 病理的机制。这该项目将测试新的假设，即 IAV 感染期间中性粒细胞的过度激活会引发破坏性的导致肌病的过度炎症反应。在第一个目标中，我们将检验以下假设： IAV 感染后活性氧化物质 (ROS) 产生的减少将通过以下方式限制损害：加强肌肉细胞-ECM 粘附，提高存活率。这将通过检查如何完成整体 ROS 减少和中性粒细胞特异性 ROS 减少改变肌肉变性、细胞-ECM 粘附、使用 IAV 多光谱荧光报告基因 (Color-flu) 菌株进行体内肌肉中中性粒细胞的定位。在第二个目标中，我们将检验以下假设：IAV 感染后中性粒细胞迁移缺陷将增加肌肉退化，削弱ECM粘附力。为了实现这一点，我们将使用体内共焦成像研究两种感染 Color-flu 的中性粒细胞迁移缺陷的斑马鱼突变体，以测试我们的假设：1) 中性粒细胞侵入骨骼肌减少，2) 肌肉退化增加并且细胞-ECM 粘附力比对照组有所增加。其中一种突变体在中性粒细胞中过度表达 miR-199 扰乱中性粒细胞迁移。提议的 RNA 测序将使我们能够确定 microRNA 基因调控网络从而使我们能够在 IAM 和 microRNA 遗传调控之间建立联系。通过 IAM 研究获得的知识可能有助于其他病毒相关肌病的研究。